Toothed gearing for driving the drum of pulley blocks



April l7, 1925. 1,532,899

F. HOLTSCHMIT TOOTHED GEARING FOR DRIVING THE DRUM OF PULLEY BLOCKS Filed Sep'c. 11, 1924 Invcntor latented Apr., 7, i925.

UNITED STATES FRIEDRICH vII'oIxrscIrIvIrII or DUIsBlUIeG, GERMANY. v l

g 1,532.89@ rPAraNrorFica..

troorHED GEARING Foa DRIVING Ina naUIe'oF rULLnY BLOCKS.'

Application :tiled September 11,v 1924. Serial No.`737,166.

June 22, 1923; Germany, August 13, 1923) of Vwhich the following is a specification.

In electrically driven pulley blocks it is known to provide the whole drive within the load drum. As, however, by reason' of the small space available, only a limited gear ratio was possible, it was necessary to drive the mechanism by means of particularly slow-running motors, which were very eX- pensive to produce. Y

Furthermore, in order ytobe able to use high-speed motors, that' is, motors of the usuall type of construction, the gear ratio has been increased bythe use of sun and planet gear wheels. In this case, however, other disadvantages have to be taken into consideration, as this type of drive is very expensive to produceand requires the most careful attention. Furthermore the mechanism makes a veryV disturbingl clatter when the sun and planet gear is running at high speeds. f

Thus, Vit has always been the endeavour to secure the necessarygear ratio by the use of simple spur wheel gears. Forthispurpose an extrashaft was provided parallel to the main shaft disposed on the center axis of the drum, and toothed wheels were provided upon both shafts ina sufficiently large number. The power was transmitted from one shaft tothe other andvbacli again according to the number of gear wheels employed. Here again the total gear ratio was insufficient. As the pressure on the gear wheel teeth increases, so must the pitch. between the pairs of gear wheels be like-wise increased and Consequently the number of teeth is correspondingly reduced, that is, according to the distance the parallel shafts are placed apart a low tot-al gear ratio is obtained whether a small or a larger number of separate gears is provided. The distance between the two shafts is limited by the small space available within the drum.

Thus it has always been necessary to dispose the main gear outside the drum by means of spur wheels or the like, and to provde Within the drum silly a portier. of the space within the drum. v y The problem` was solved lby mounting the shafts of the spur wheels forming the trans necessary gears as well as the drum drivingmechanism itself.

This gave an unprepossessmg appearance to the pulleybl'oclg and inaddition theretoy the gearing outside the drum was easily Furthermore, in all these constructions there is the disadvantage common to the construction as a whole and to the separate parts of the gearing that the gearing .can be dismantled only by the withdrawal of each gear element and it can' only beV assembled within the drum. Y

The present invention has for` its object to secure a transmission of-high gear ratio in the use of simple spur wheels, and at the same time'to provide the gear parts in their entirety within the drum in such manner that they can be readily assembled anddismantled Aand occupy the smallest possible mission gearing disposed arou-nd the main driving shaftv disposed within vthe drum. Y

By such means ,not only. are theincon-v veniences' in the knownconstruction hereinbefore referred to avoided, but the spacek 4 available -within the drum vis completely madeuse of. The whole transmission needsV only a very smallportion of the space'` within the drum. The. remaining space Vmay be4 used for other useful purposes'.`

,According to theV invention the gearing is mounted' upon thev cover plate which closes the drum in suchlmanner as to form with the cover plate a singleunit, that is as a complete construct-ional element. lThus the gearing may be readily exchanged and replaced at all times, but the most impor-` tant advantage is in the manufacture. It is thus now possible to have the gearing tested and reset. A further advantage is that every wheel shaft may be supported at both ends.

' It will be readily apparent that the safety of operation of the gearing is considerably increased as 'compared with the gears in :which the wheel shafts are mountedV at one end only. VVith a view to facilitating the supply of lubricant from the outside, the

^ shafts of the separate wheels are arranged One'construction of apparatus according t@ the invention for use @e electrically driven "pulley 'block is illustratedfby Way of example' in the accompanying diagrammatic drawings in' Which'- FigLl is a sideelevation, ,partly in section, on the line l-l' of Fig. '2, shovvingan ap paiatus embodying 'my invention-g Fig. 2 is an end view of the apparatus, looking from left Ito right in Fig. '1,' the outer cap and parts externa-l to the end piece 'of the casing 'being 'omitted and the gears Within the casing heilig indicatedvin 'dotted fFig. '3 is a Vsection -on the line 'of rFig. '2

vided. rWithin the drn1ns- (on the rightlieiid Side) rthere 5is provided 'the driving `notora the shaft 4 of which is coupled vto shaft 6 of the gearing by ithe coupling 5.V

Shaft l'6 carries fai pinion 7 jan-d is mounted on 'bethsdes thereof iin 'bal-'l bearings 9 andV t@ in the' 'coiver plate '8. rThe fbralke magnet l2 'lis suspended "t1-'om and `4outside' the A'cover plate 8 and the brake drum 13 .is mounted nffjoii the shaft 6. 'The driving pinion? engagesf'wth the toothed Wheel i4, which lis integrml, with 'pinion 1F5 and is loosely f mounted to Yrotate V'upon#the shaft d6. rThis sliwftl is flitkew'v-ise snpported, `upon -hoth `sides ef' the wheels-14. and Yi115, et ie I19 `in the cov'ei' plate. The piniony l5 Lengageswith Y 120th fthe v@over p'lateS. Thepinien() engages with the Wheel l22 (see Figsgf and 4)', Whicth'is integral With the pinion 2B and is mounted upon the shaft 24. The pinion 23 is in engagement with the intermediate Wheel 25 mounted' upon the shaft 26. The' :Wheel125 transmits-motion :to the integrally Course, be understood that the invention is 'not Vlimited to the embodiment Vherein- "befor'e describedjfor -exzumplefthe braking mechanism #may be provldedseparate `trom 'the oever 3plate and likewise the n'u'nfibeij` :of

the spur Wheels -utilized is 'of no consequence 'to the essential feature of -the invention,

which lis lconcerned lwith 'the inecessary geen" initio..

I claim The combifnationavitli a-'casin'g andra diium f rotatably mounted therein, said drum'having an internal 'geaigfo'f 'removable endpiece Y fc-,losing lone end oflthe casing'and 'having a shaftesulpporting trame projecting fntorth-e 'interior et tliefdinmm drive'shaft :rotatably mounted in said frame yat 'the =a`xis of the drive' lshai't, said ixed shaflts Aextending gthrough the end piece-Fand p'lovid'ed with oil holes external thereto, a pinion on the drive 'shatg and `a train of gearing/on said lixed nennen-.ion iioLTsoHMiT. y

'shafts connectingrsaiidpinion "With saidin'- -temia'l gear. v l Y 

